ka24 headgasket lower chain fell - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

robbie2883 · 08-17-2011, 12:17 AM

ok...i did alot of searching...it's late and maybe i'm just tired and impatient but can't find the answer i'm looking for. so if it's out there i'm sorry for asking in advance

anyway....i'm helping a friend do a headgasket on a 97 dohc. everything was going smooth. got the head off...zip tied the lower chain to the idler pulley and left the it in the guides so the tension would pick up the slack. left ift for the night and told them to clean the surfaces so when i come back we can slap the head back on......well i come back and the knocked the lower chain out of the guides and the tensioner fully extended jamming the chain between the front cover and the guides.

now here's my Q. if i can get the thing unjammed does the lower timing gear have a stopper on the bottom to keep the chain from dropping off the teeth or do i need to just go ahead and pull the pan and front cover? also the tension seems stuck full extended...it's just a hydrolic spring correct? any tips on compressing it? thanks in advance...i absolutely hate asking stupid questions like this.

robbie2883 · 08-17-2011, 10:31 AM

bump....anyone?

orion::S14 · 08-17-2011, 02:24 PM

The lower sprocket WILL allow the chain to come off.

As long as you verify the motor is at TDC on #1...and get the upper timing chain (cam timing) dead-on...it's really of no consequence.

But you'll have to install, rotate the motor, check....and double check to be sure that you put the lower timing chain on at TDC on #1.

It'll be a bitch if you get it wrong.

Might be easier to pull the lower cover now and fix it right.

- Brian

robbie2883 · 08-17-2011, 09:53 PM

thanks for the info....just messed with it again tonight. i decided to try something different...put the head back on and bolted the idle pulley back in...turned the motor over a few times till the orange link lined up with the mark on the idle pulley. set the crank to the orange 0 degree mark then set the cam chain on the marks for tdc. turned over by hand a few times and nothing hit....yay! LOL

keytops · 08-18-2011, 02:37 AM

A bore scope works real well for this. Good job averting crisis.

08-17-2011, 02:24 PM	#3
orion::S14 Nissanaholic! Join Date: May 2003 Location: Orange Park, FL Posts: 1,666 Trader Rating: (0) Feedback Score: 0 reviews	The lower sprocket WILL allow the chain to come off. As long as you verify the motor is at TDC on #1...and get the upper timing chain (cam timing) dead-on...it's really of no consequence. But you'll have to install, rotate the motor, check....and double check to be sure that you put the lower timing chain on at TDC on #1. It'll be a bitch if you get it wrong. Might be easier to pull the lower cover now and fix it right. - Brian __________________ www.KA24DEvelopment.com

08-17-2011, 12:17 AM	#1
robbie2883 Zilvia Member Join Date: Jan 2009 Location: FL Posts: 252 Trader Rating: (1) Feedback Score: 1 reviews	ka24 headgasket lower chain fell ok...i did alot of searching...it's late and maybe i'm just tired and impatient but can't find the answer i'm looking for. so if it's out there i'm sorry for asking in advance anyway....i'm helping a friend do a headgasket on a 97 dohc. everything was going smooth. got the head off...zip tied the lower chain to the idler pulley and left the it in the guides so the tension would pick up the slack. left ift for the night and told them to clean the surfaces so when i come back we can slap the head back on......well i come back and the knocked the lower chain out of the guides and the tensioner fully extended jamming the chain between the front cover and the guides. now here's my Q. if i can get the thing unjammed does the lower timing gear have a stopper on the bottom to keep the chain from dropping off the teeth or do i need to just go ahead and pull the pan and front cover? also the tension seems stuck full extended...it's just a hydrolic spring correct? any tips on compressing it? thanks in advance...i absolutely hate asking stupid questions like this.

08-17-2011, 10:31 AM	#2
robbie2883 Zilvia Member Join Date: Jan 2009 Location: FL Posts: 252 Trader Rating: (1) Feedback Score: 1 reviews	bump....anyone?

08-17-2011, 09:53 PM	#4
robbie2883 Zilvia Member Join Date: Jan 2009 Location: FL Posts: 252 Trader Rating: (1) Feedback Score: 1 reviews	thanks for the info....just messed with it again tonight. i decided to try something different...put the head back on and bolted the idle pulley back in...turned the motor over a few times till the orange link lined up with the mark on the idle pulley. set the crank to the orange 0 degree mark then set the cam chain on the marks for tdc. turned over by hand a few times and nothing hit....yay! LOL